Spin Pumping and Inverse Spin Hall Effect in Topological Dirac Semimetals

We study the time-development processes of spin and charge transport phenomena in a topological Dirac semimetal attached to a ferromagnetic insulator with a precessing magnetization. Topological Dirac semimetals manifest a large inverse spin Hall effect when a spin current is pumped from the attached ferromagnetic insulator, compared to conventional normal metals. While the pumped spin current is affected by disorder, the induced charge current hardly depends on the disorder strength. This result indicates that the robustness originates to topological properties of the topological Dirac semimetals, such as the helical Fermi arc states at the interface.